Effectiveness of Repetitive Transcranial Magnetic Stimulation on Fibromyalgia Patients Responding to a First Repetitive Transcranial Magnetic Stimulation Induction Course After Six Months of Maintenance Treatment: A Randomized Pilot-Controlled Study

Background: Fibromyalgia is a chronic painful condition without real, effective treatment. The administration of repetitive transcranial magnetic stimulation (rTMS) has been shown to have a therapeutic effect on pain, but there are still questions about the maintenance of its effect over time. Continuation of the treatment upon clinical response through maintenance sessions is promising and merits further exploration. Materials and Methods: We conducted a randomized, parallel-group, controlled study involving 78 patients to evaluate the effect of rTMS vs sham stimulation after a three-week induction treatment and six months of maintenance treatment (three-week periodicity) on 22 patients who presented a clinical response to the induction treatment. The clinical response was defined as a >= 30% decrease of the baseline visual analog scale (VAS) for pain and a score for the Patient Global Impression of Change (PGIC) >5. The clinic global impression, fibromyalgia impact questionnaire, symptom severity score, and Beck's depression inventory were also studied. Results: A significant clinical response to treatment with rTMS was observed after the induction phase and maintained over six months, particularly as measured by the PGIC parameter of pain, as well as of the intensity of fatigue and depression, with an absence of adverse effects induced by this method. Conclusion: A three-week rTMS treatment, characterized by a reduction in pain, as evaluated by VAS, should be continued with the administration of rTMS maintenance sessions for an additional six months to maintain the best possible long-term effects.